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Nonogaki K. The Regulatory Role of the Central and Peripheral Serotonin Network on Feeding Signals in Metabolic Diseases. Int J Mol Sci 2022; 23:ijms23031600. [PMID: 35163521 PMCID: PMC8836087 DOI: 10.3390/ijms23031600] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/25/2022] [Accepted: 01/28/2022] [Indexed: 11/16/2022] Open
Abstract
Central and peripheral serotonin (5-hydroxytryptamine, 5-HT) regulate feeding signals for energy metabolism. Disruption of central 5-HT signaling via 5-HT2C receptors (5-HT2CRs) induces leptin-independent hyperphagia in mice, leading to late-onset obesity, insulin resistance, and impaired glucose tolerance. 5-HT2CR mutant mice are more responsive than wild-type mice to a high-fat diet, exhibiting earlier-onset obesity and type 2 diabetes. High-fat and high-carbohydrate diets increase plasma 5-HT and fibroblast growth factor-21 (FGF21) levels. Plasma 5-HT and FGF21 levels are increased in rodents and humans with obesity, type 2 diabetes, and non-alcohol fatty liver diseases (NAFLD). The increases in plasma FGF21 and hepatic FGF21 expression precede hyperinsulinemia, insulin resistance, hyperglycemia, and weight gain in mice fed a high-fat diet. Nutritional, pharmacologic, or genetic inhibition of peripheral 5-HT synthesis via tryptophan hydroxylase 1 (Tph1) decreases hepatic FGF21 expression and plasma FGF21 levels in mice. Thus, perturbing central 5-HT signaling via 5-HT2CRs alters feeding behavior. Increased energy intake via a high-fat diet and/or high-carbohydrate diet can upregulate gut-derived 5-HT synthesis via Tph1. Peripheral 5-HT upregulates hepatic FGF21 expression and plasma FGF21 levels, leading to metabolic diseases such as obesity, insulin resistance, type 2 diabetes, and NAFLD. The 5-HT network in the brain–gut–liver axis regulates feeding signals and may be involved in the development and/or prevention of metabolic diseases.
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Affiliation(s)
- Katsunori Nonogaki
- Laboratory of Diabetes and Nutrition, New Industry Creation Hatchery Center, Tohoku University, Sendai 980-8579, Japan
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Maejima Y, Yokota S, O'Hashi R, Aoyama M, Shimomura K. The effect of avertin anesthesia and a mixture of three types of anesthetic agents on food intakeand body weight in high fat-induced obese maleand female mice. Exp Anim 2018; 68:57-69. [PMID: 30210091 PMCID: PMC6389510 DOI: 10.1538/expanim.17-0145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Basic research on obesity is becoming more important due to an increasing number of obese
people. Experiments using obesity-model animals often require surgical interventions, such
as gastric operation, and proper selection of anesthesia is important. Avertin, an agent
mainly composed of 2,2,2-Tribromoethanol, has been used as general anesthesia for a long
time, without the use of narcotic drugs. In the current study, we found that a single
injection of avertin can decrease body weight (BW) in male and female C57BL/6J and ICR
mice with high fat-diet (HFD)-induced obesity, but not in standard diet-fed nonobese males
and females. Because the BW-reducing effect was more prominent in the female mice, we
compared the effects of avertin and a mixture of three types of anesthetic agents (3MIX),
which was developed in 2011, on BW reduction in HFD-induced obese female mice. Although
both avertin and 3MIX decreased food intake and BW, the effects of avertin were
significantly more potent than those of 3MIX. C-Fos expression, a neural activation
marker, was dramatically increased in the brain regions related to the regulation of both
food intake and the autonomic nervous system after avertin injection, but not after 3MIX
injection. This suggests that avertin strongly stimulates the center of feeding regulation
and the autonomic nervous system and therefore decreases BW. The current study suggests
the advantages of using 3MIX for surgical interventions in mice in obesity research, as it
is ideal to prevent anesthesia-induced BW decline.
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Affiliation(s)
- Yuko Maejima
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, 1 Hikarigaoka, Fukushima-shi, Fukushima 960-1295, Japan
| | - Shoko Yokota
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, 1 Hikarigaoka, Fukushima-shi, Fukushima 960-1295, Japan
| | - Rie O'Hashi
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, 1 Hikarigaoka, Fukushima-shi, Fukushima 960-1295, Japan
| | - Masato Aoyama
- Department of Animal Science, Faculty of Agriculture, Utsunomiya University, 350 Minemachi, Utsunomiya-shi, Tochigi 321-8505, Japan
| | - Kenju Shimomura
- Department of Bioregulation and Pharmacological Medicine, Fukushima Medical University School of Medicine, 1 Hikarigaoka, Fukushima-shi, Fukushima 960-1295, Japan
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Windham BG, Fumagalli S, Ble A, Sollers JJ, Thayer JF, Najjar SS, Griswold ME, Ferrucci L. The Relationship between Heart Rate Variability and Adiposity Differs for Central and Overall Adiposity. J Obes 2012; 2012:149516. [PMID: 22649714 PMCID: PMC3357556 DOI: 10.1155/2012/149516] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 02/23/2012] [Accepted: 02/23/2012] [Indexed: 12/31/2022] Open
Abstract
While frank obesity is associated with reduced HRV, indicative of poorer autonomic nervous system (ANS) function, the association between body mass index (BMI) and HRV is less clear. We hypothesized that effects of adiposity on ANS are mostly mediated by visceral fat and less by subcutaneous fat; therefore, centrally distributed adipose tissue, that is, waist circumference (WC), should be more strongly associated with HRV than overall adiposity (BMI). To examine this hypothesis, we used data collected in a subset of the Baltimore Longitudinal Study of Aging to compare strength of association between HRV and WC to that of HRV and BMI. Time domain HRV variables SDNN (standard deviation of successive differences in normal-to-normal (N-N) intervals) and RMSSD (root mean square of successive differences in N-N intervals) were calculated from 24-hour Holter recordings in 159 participants (29-96 years). Increasing WC was associated with decreasing SDNN and RMSSD in younger but not older participants (P value for WC-by-age interaction = 0.003). BMI was not associated with either SDNN or RMSSD at any age. In conclusion, central adiposity may contribute to sympathetic and parasympathetic ANS declines early in life.
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Affiliation(s)
- B. Gwen Windham
- Division of Geriatrics, Department of Medicine, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Stefano Fumagalli
- Unit of Geriatrics, Department of Critical Care Medicine and Surgery, University of Florence and AOU Careggi, 50134 Florence, Italy
| | - Alessandro Ble
- Clinical Research Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21225-1290, USA
| | - John J. Sollers
- Department of Psychological Medicine, Faculty of Medical & Health Science, The University of Auckland, Auckland 1142, New Zealand
| | - Julian F. Thayer
- The Ohio State University, Columbus, OH 43210, USA
- *Julian F. Thayer:
| | - Samar S. Najjar
- Clinical Research Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21225-1290, USA
- Laboratory of Cardiovascular Science, Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Michael E. Griswold
- Center of Biostatistics and Bioinformatics, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Luigi Ferrucci
- Clinical Research Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21225-1290, USA
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Akana SF. Feeding and stress interact through the serotonin 2C receptor in developing mice. Physiol Behav 2008; 94:569-79. [DOI: 10.1016/j.physbeh.2008.03.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Revised: 03/24/2008] [Accepted: 03/24/2008] [Indexed: 12/14/2022]
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Makinodan K, Yoshikawa M, Fukuoka A, Tamaki S, Koyama N, Yamauchi M, Tomoda K, Hamada K, Kimura H. Effect of Serum Leptin Levels on Hypercapnic Ventilatory Response in Obstructive Sleep Apnea. Respiration 2008; 75:257-64. [DOI: 10.1159/000112471] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Accepted: 08/28/2007] [Indexed: 11/19/2022] Open
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Miranda LP, Shao H, Williams J, Chen SY, Kong T, Garcia R, Chinn Y, Fraud N, O'Dwyer B, Ye J, Wilken J, Low DE, Cagle EN, Carnevali M, Lee A, Song D, Kung A, Bradburne JA, Paliard X, Kochendoerfer GG. A Chemical Approach to the Pharmaceutical Optimization of an Anti-HIV Protein. J Am Chem Soc 2007; 129:13153-9. [DOI: 10.1021/ja073982h] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Les P. Miranda
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Haiyan Shao
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Jason Williams
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Shiah-Yun Chen
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Ting Kong
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Rod Garcia
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Yvonne Chinn
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Nathalie Fraud
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Bill O'Dwyer
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Jay Ye
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Jill Wilken
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Donald E. Low
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - E. Neil Cagle
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Maia Carnevali
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Alexander Lee
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Di Song
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Ada Kung
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - James A. Bradburne
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Xavier Paliard
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
| | - Gerd G. Kochendoerfer
- Contribution from Gryphon Therapeutics, 600 Gateway Boulevard, South San Francisco, California 94080
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Abstract
Social isolation is associated with increased risks of mortality and morbidity. In this study, we show that chronic individual housing accelerated body weight gain and adiposity in KK mice but not C57BL6J mice, and fully developed diabetes in KKA(y) mice. Individually housed KK and KKA(y) mice increased body weight gain over the initial 2 wk without increased daily average food consumption compared with group-housed animals. The individually housed KK and KKA(y) mice then gradually increased food consumption for the next 1 wk. The chronic social isolation-induced obesity (SIO) was associated with hyperleptinemia and lower plasma corticosterone and active ghrelin levels but not hyperinsulinemia. Elevated plasma leptin in the SIO suppressed expression of 5-HT2C receptor in white adipose tissue. The SIO was also associated with decreased expression of beta3-adrenergic receptors in white adipose tissue and hypothalamic leptin receptor, which might be secondary to the enhanced adiposity. Interestingly, social isolation acutely reduced food consumption and body weight gain compared with group-housed obese db/db mice with leptin receptor deficiency. Social isolation-induced hyperglycemia in KKA(y) mice was associated with increased expression of hepatic gluconeogenetic genes independent of insulin. These findings suggest that social isolation promotes obesity due to primary decreased energy expenditure and secondary increased food consumption, which are independent of the disturbed leptin signaling, in KK mice, and develops into insulin-independent diabetes associated with increased expression of hepatic gluconeogenetic genes in KKA(y) mice. Thus, social isolation can be included in the environmental factors that contribute to the development of obesity and type 2 diabetes.
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Affiliation(s)
- Katsunori Nonogaki
- Associate Professor, Center of Excellence, Division of Molecular Metabolism and Diabetes, Tohoku University Graduate School of Medicine, 2-1 Seiryou-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan.
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Whitson BA, Leslie DB, Kellogg TA, Maddaus MA, Buchwald H, Billington CJ, Ikramuddin S. Adipokine response in diabetics and nondiabetics following the Roux-en-Y gastric bypass: a preliminary study. J Surg Res 2007; 142:295-300. [PMID: 17640666 DOI: 10.1016/j.jss.2007.03.036] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 03/19/2007] [Accepted: 03/20/2007] [Indexed: 11/30/2022]
Abstract
INTRODUCTION The adipocyte influences eating behavior and metabolism via cytokine secretion. We report our findings of adipokine secretion in a cohort of diabetic and nondiabetic morbidly obese patients before and after Roux-en-Y gastric bypass (RYGB). METHODS Ten morbidly obese subjects who underwent uncomplicated RYGB were studied: five were diabetic and nine were female. Nonfasting plasma levels of adiponectin, resistin, leptin, and tumor necrosis factor-alpha were determined preoperatively and 6 mo postoperatively. C-reactive protein (CRP) was followed as a marker of the metabolic syndrome. RESULTS The patient age was 42 +/- 11 y, and the preoperative BMI was 50 +/- 6 kg/m(2). The 6 mo BMI fell to 33 +/- 5 kg/m(2) (P < 0.0001), and there were no differences between diabetics and nondiabetics with respect to amount of weight loss. In nondiabetic patients, there were significant increases compared with preoperative levels for adiponectin, resistin, and tumor necrosis factor-alpha; leptin was significantly decreased while CRP was unchanged. CRP and leptin levels were both significantly lower (P < 0.05), while all other protein levels were unchanged in diabetic patients. CONCLUSIONS At 6 mo postoperation, RYGB significantly altered most adipokine levels for nondiabetic patients. Only CRP and leptin were changed in diabetic patients. All patients lost a significant amount of weight over 6 mo, suggesting a different metabolic effect between nondiabetic and diabetic patients after RYGB.
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Affiliation(s)
- Bryan A Whitson
- University of Minnesota Department of Surgery, Division of Gastrointestinal Surgery, Minneapolis, Minnesota 55455, USA
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9
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Yoshimura R, Omori H, Somekawa S, Osaka T, Ito R, Inoue S, Endo Y. Continuous carbachol infusion promotes peripheral cell proliferation and mimics vagus hyperactivity in a rat model of hypothalamic obesity. Biomed Res 2006; 27:81-8. [PMID: 16707847 DOI: 10.2220/biomedres.27.81] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Lesions of the ventromedial hypothalamus (VMH) result in obesity and enhanced cellular proliferation in various organs, including the pancreas, gastrointestinal tract, and liver. Previous studies have suggested that vagal hyperactivity, rather than overeating, induces the peripheral cell proliferation in VMH-lesioned rats. The goal of the present study was to investigate the mechanism of peripheral cell proliferation in VMH-lesion-induced obesity by infusing rats with the acetylcholine agonist, carbachol, and then measuring cellular proliferation in the pancreas and duodenum using immunohistochemistry. The ventromedial hypothalamus was bilaterally lesioned in five rats. In other rats, the bilateral vagus nerves were ligated (vagotomized), and saline or carbachol was continuously administered by an osmotic minipump (n = 5 in each group). Three days later, rats were killed, and cell proliferation was assessed in the pancreas and the duodenum using immunohistochemistry for proliferating cell nuclear antigen (PCNA). Additionally, cellular proliferation in the duodenum was more precisely examined by assessing incorporation of 5-bromo-2'-deoxyuridine (BrdU). Cellular proliferation was higher in rats that received carbachol infusions and in rats with VMH-lesions when compared with control rats (P < 0.05, respectively). The pancreatic PCNA-expressing cells were predominantly identified as the B-cells of the islets of Langerhans. These data demonstrate that carbachol infusion can induce pancreatic and duodenal cell proliferation to a degree that was comparable to that in vagal hyperactivity induced by VMH lesions.
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Affiliation(s)
- Ryoichi Yoshimura
- Department of Applied Biology, Kyoto Institute of Technology, Kyoto, Japan.
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Gordon P, Sanders MH. Sleep.7: positive airway pressure therapy for obstructive sleep apnoea/hypopnoea syndrome. Thorax 2005; 60:68-75. [PMID: 15618587 PMCID: PMC1747175 DOI: 10.1136/thx.2003.007195] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The use of continuous positive airway pressure (CPAP) in treating symptoms associated with OSAHS is reviewed. Although it is an imperfect intervention, it continues to evolve and improve in such a way that patients who would not have been able to use this treatment even in the recent past can benefit from it today.
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Affiliation(s)
- P Gordon
- Critical Care and Sleep Medicine, University of Pittsburgh School of Medicine, Montefiore University Hospital, North-1292, Pittsburgh, PA 15213, USA
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Abstract
A few examples of hypothalamic, peptidergic disorders leading to clinical signs and symptoms are presented in this review. Increased activity of corticotropin-releasing hormone (CRH) neurons in the paraventricular nucleus (PVN) and decreased activity of the vasopressin neurons in the biological clock and of the thyroxine-releasing hormone (TRH) neurons in the PVN contribute to the signs and symptoms of depression. In men, the central nucleus of the bed nucleus of the stria terminalis (BSTc) is about twice as large and contains twice as many somatostatin neurons as in women. In transsexuals this sex difference is reversed, pointing to a role of this structure in gender. Luteinizing hormone-releasing hormone (LHRH) neurons are formed in the fetal olfactory placade and migrate along the terminal nerve fibers into the hypothalamus. In Kallmann's syndrome the migration process of the LHRH (gonadotropin-releasing hormone) neurons is aborted, which explains the joint occurrence of hypogonadotropic hypogonadism and anosmia in this syndrome. In postmenopausal women, the neurons of the infundibular nucleus hypertrophy and become hyperactive because of the disappearance of the estrogen feedback and contain hyperactive peptidergic neurons. Climacteric flushes may be caused by hyperactivity of the neurokinin-B or LHRH neurons in this nucleus. The hypocretin (orexin) neurons in the perifornical area are involved in sleep. In narcolepsy with cataplexy, a loss of these neurons, probably due to an autoimmune process, is found. Obese subjects with a mutation in the gene that encodes for leptin, the preproghrelin gene, or the alpha-melanocyte-stimulating hormone (alpha-MSH) gene have been described. Decreased numbers and activity of the oxytocin neurons in the PVN may be responsible for the absence of satiety in Prader-Willi syndrome. Moreover, a glucocorticoid receptor polymorphism is associated with obesitas and dysregulation of the hypothalamus-pituitary-adrenal axis. In contrast, two single nucleotide polymorphisms (SNPs) of the AGRP gene have been associated with anorexia nervosa.
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Affiliation(s)
- Dick F Swaab
- Netherlands Institute for Brain Research, 1105 AZ, Amsterdam, The Netherlands
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Raposinho PD, White RB, Aubert ML. The melanocortin agonist Melanotan-II reduces the orexigenic and adipogenic effects of neuropeptide Y (NPY) but does not affect the NPY-driven suppressive effects on the gonadotropic and somatotropic axes in the male rat. J Neuroendocrinol 2003; 15:173-81. [PMID: 12535159 DOI: 10.1046/j.1365-2826.2003.00962.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neuropeptide Y (NPY) is a strong orexigenic neurotransmitter also known to modulate several neuroendocrine axes. alpha-Melanocyte-stimulating hormone (MSH) is an essential anorectic neuropeptide, acting on hypothalamic MC3/4 receptor subtypes. When given as an intracerebroventricular bolus injection, Melanotan-II (MT-II), a non selective MC receptor agonist, inhibits feeding, suppresses the NPY orexigenic action, and reduces basal insulinaemia. We evaluated the effects of a 7-day central infusion of MT-II (15 nmol/day) given either alone or in association with NPY (5 nmol/day) in male Sprague-Dawley rats. MT-II produced almost full anorexia for 1-2 days but then feeding gradually returned to normal despite continued MT-II infusion. When coinfused with NPY, MT-II also produced the same initial anorectic episode but then maintained feeding to upper normal levels, thus cancelling the hyperphagia driven by NPY. Whereas NPY infusion produced a doubling of fat pad weight, MT-II reduced adiposity by a factor of two compared to pair-fed rats, and vastly curtailed the NPY-driven increase in fat pad weight. MT-II infusion also significantly curtailed the NPY-induced rise in insulin and leptin secretions. NPY infusion significantly inhibited hypothalamic pro-opiomelanocortin mRNA expression, most likely cancelling the alpha-MSH anorectic activity. As expected from previous studies, chronic NPY infusion strongly inhibited both the gonadotropic and somatotropic axes, and coinfusion of MT-II did not reverse these NPY-driven effects, in sharp contrast with that seen for the metabolic data. MT-II infusion alone had little effect on these axes. In conclusion, chronic MT-II infusion generated a severe but transient reduction in feeding, suggesting an escape phenomenon, and clearly reduced fat pad size. When coinfused with NPY, MT-II was able to cancel most of the NPY effects on feeding, but not those on the neuroendocrine axes. It appears therefore that, as expected, NPY and alpha-MSH closely interact in the control of feeding, whereas the neural pathways by which NPY affects growth and reproduction are distinct and not sensitive to MC peptide modulation.
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Affiliation(s)
- P D Raposinho
- Division of Development and Growth, Department of Pediatrics, University of Geneva School of Medicine, Geneva, Switzerland
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Rodríguez AM, Quevedo-Coli S, Roca P, Palou A. Sex-dependent dietary obesity, induction of UCPs, and leptin expression in rat adipose tissues. OBESITY RESEARCH 2001; 9:579-88. [PMID: 11557839 DOI: 10.1038/oby.2001.75] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The aim of this study was to determine the sex-dependent differences in the response of key parameters involved in thermogenesis and control of body weight in brown adipose tissue (BAT) and white adipose tissue (WAT) in postcafeteria-fed rats, a model of dietary obesity. RESEARCH METHODS AND PROCEDURES BAT and WAT were obtained from male and female control and postcafeteria-fed Wistar rats. Postcafeteria-fed rats were initially fed with cafeteria diet from day 10 of life until day 110 (cafeteria period) and with standard chow diet from then until day 180 of life (postcafeteria period). Body mass and energy intake were evaluated. Biometric parameters were analyzed in interscapular BAT (IBAT). Levels of uncoupling protein 1 (UCP1), alpha(2)-adrenergic receptor (AR), and beta(3)-AR proteins and UCP1, UCP2, UCP3, beta(3)-AR, and leptin mRNAs, in IBAT or WAT, were studied by Western blot and Northern blot analyses, respectively. RESULTS Rats attained 59% (females) and 39% (males) increase in body weight at the end of the cafeteria period. During the postcafeteria period, the rats showed a loss of body weight, which was higher in females. Postcafeteria-fed female rats also presented higher activation of thermogenic parameters in IBAT, including UCP1, UCP2, and UCP3 mRNAs. Female control rats showed lower levels of both alpha 2 and beta(3)-ARs in BAT compared with male rats, but these levels in postcafeteria-fed female and male rats were the same, because males tended to down-regulate them. Levels of leptin mRNA in response to the postcafeteria state depended on gender and the specific WAT depot studied. DISCUSSION It is suggested that in postcafeteria-fed female rats, BAT thermogenic capacity becomes more efficiently activated than in males. Female rats also showed a bigger weight loss. The parallel regulation of the levels of UCP2 and UCP3 mRNAs, with respect to UCP1 mRNA, with higher activation in female postcafeteria-fed rats, suggests a possible role of both UCP2 and UCP3 in the regulation of energy expenditure and in the control of body weight. The distinct responses to overweight of alpha 2 and beta(3)-ARs--which were sex dependent--and leptin mRNA--which depended on both sex and WAT depot--also support the different response of thermogenesis-related parameters between overweight males and females.
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Affiliation(s)
- A M Rodríguez
- Departament de Biologia Fonamental i Ciències de la Salut, Laboratori de Biologia Molecular, Nutrició i Biotecnologia, Universitat de les Illes Balears, Palma de Mallorca, Spain
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14
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Pirson I, Fortemaison N, Jacobs C, Dremier S, Dumont JE, Maenhaut C. The visual display of regulatory information and networks. Trends Cell Biol 2000; 10:404-8. [PMID: 10998591 DOI: 10.1016/s0962-8924(00)01817-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Cell regulation and signal transduction are becoming increasingly complex, with reports of new cross-signalling, feedback, and feedforward regulations between pathways and between the multiple isozymes discovered at each step of these pathways. However, this information, which requires pages of text for its description, can be summarized in very simple schemes, although there is no consensus on the drawing of such schemes. This article presents a simple set of rules that allows a lot of information to be inserted in easily understandable displays.
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Affiliation(s)
- I Pirson
- Institute of Interdisciplinary Research, Free University of Brussels, Campus Erasme, 808 route de Lennik, B-1070 Brussels, Belgium
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15
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Phillips BG, Kato M, Narkiewicz K, Choe I, Somers VK. Increases in leptin levels, sympathetic drive, and weight gain in obstructive sleep apnea. Am J Physiol Heart Circ Physiol 2000; 279:H234-7. [PMID: 10899061 DOI: 10.1152/ajpheart.2000.279.1.h234] [Citation(s) in RCA: 228] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Patients with obstructive sleep apnea (OSA) are frequently obese and are predisposed to weight gain. They also have heightened sympathetic drive. We reasoned that noradrenergic activation of beta(3)-receptors on adipocytes would inhibit leptin production, predisposing to obesity in sleep apnea. We therefore tested the hypothesis that obesity and predisposition to weight gain in OSA are associated with low levels of plasma leptin. We prospectively studied 32 male patients (43 +/- 2 yr) with OSA who were newly diagnosed and never treated and who were free of any other diseases. Control measurements were obtained from 32 similarly obese closely matched male subjects (38 +/- 2 yr). Leptin levels were 13.7 +/- 1.3 and 9.2 +/- 1.2 ng/ml in patients with OSA and controls, respectively (P = 0.02). Weight gain over the year before diagnosis was 5.2 +/- 1.7 and 0.5 +/- 0.9 kg in sleep apnea patients and similarly obese control subjects, respectively (P = 0.04). Muscle sympathetic activity was 46 +/- 4 and 30 +/- 4 bursts/min in patients with OSA (n = 16) and control subjects (n = 18), respectively (P = 0.01). Plasma leptin levels are elevated in newly diagnosed otherwise healthy patients with untreated sleep apnea beyond the levels seen in similarly obese control subjects without sleep apnea. Higher leptin levels in OSA, independent of body fat content, suggest that OSA is associated with resistance to the weight-reducing effects of leptin.
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Affiliation(s)
- B G Phillips
- Division of Clinical and Administrative Pharmacy, College of Pharmacy, University of Iowa, Iowa City, Iowa 52242, USA
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